The present invention relates to a method for controlling a vehicle, said vehicle having a system being connected with a position input connection for receiving vehicle position information from a positioning system, a map database, a driver information database, and an output connection.
The invention also relates to a system comprising the above stated components and a vehicle.
Within the vehicle industry, many systems are currently being developed for assisting a driver to keep an appropriate vehicle speed. The most straightforward systems are the cruise control systems, keeping a vehicle at a pre-set speed, unless the driver overrides the system by, for example, engaging the brake. However, in certain situations, such as sharp curves or intersections, the driver might want to have a somewhat lower speed than said pre-set speed in order to comfortably and safely pass the obstacle. A problem however is that most cruise control systems are suspended when a driver presses the brake, wherefore the system needs to be reactivated after passing the obstacle in order to continue driving at said pre-set speed. Consequently, the systems have to be continuously monitored and set by the driver.
Some efforts have thereby been put into system which automatically adapt the speed of the vehicle based on national speed limits. However, vehicle drivers all have individual speed control behaviours, based on their own preferences and driving conditions and these are seldom at the same speed as the speed limits. All of the above mentioned drawbacks with prior art systems have resulted in a rather low user acceptance for the prior-art speed control systems.
Consequently, the object of the present invention is to provide a method and a system for cruise controlling a vehicle, providing a flexible solution overcoming the above mentioned drawbacks with the prior-art systems.
These and other objects are achieved by a method as stated by way of introduction, with the method comprising the following steps: receiving vehicle position information via a position input connection, extracting, from a map database, map information relating to at least one of a current and an upcoming road section, based on the vehicle position information, extracting, from a driver information database, information regarding previous driver behavior for at least one of a current road section and a similar road section, generating, based on information from an input connection, the map database and the driver information database, a speed plan for at least one of the current and upcoming road section, and outputting, via the output connection, a speed plan. By such a method it is possible to generate a speed plan, which may be used to adapt the speed of the vehicle for a chosen road section in a suitable manner. The speed plan may be used to manually or autonomously control the vehicle. By generating a speed plan for a current and/or upcoming road section, based on map data as well as user preferences as stored in the driver information database, the vehicle may driven in a comfortable and safe way as experienced by the driver.
Preferably, the method further comprises the step of: generating a driver behavior model, based on information from the input connection, the map database and the driver information database, whereby the speed plan is generated from the driver behavior model.
Preferably, the method comprises the steps of: extracting, from the map data base, one or more road attributes for the current and/or upcoming road section, and relating the road attributes to the driver behavior model. By doing this, the size of the map database may be made smaller, since only said attributes need to be stored.
In accordance with a preferred embodiment, the step of generating a driver behavior model comprises the step of: deriving the model by relating one or more road section attributes, extracted from said map database, to driver speed behavior, by using a neural network device. This makes it possible to predict speed plans for roads never driven before, by relating it to other road sections having similar road attributes, as stored in the map database.
The method further comprises the step of inputting, to said driver information database, a driver identification signal from a driver identification module, said signal being used to provide an individual driver information database for each user of the vehicle. Thereby, it is possible to adapt the generated to speed plan to the current driver of the vehicle.
In accordance with a preferred embodiment, the method comprises the step of feeding said outputted speed plan to a throttle control device, for controlling the throttle of a vehicle based on said speed plan. As an alternative or complement, the method may comprise the step of feeding said outputted speed plan to a brake system control device, for controlling the brake system of the vehicle based on the speed plan. Thereby, the vehicle may be autonomously controlled, taking under consideration personal driver style and road characteristics. As a further alternative or complement, the method may comprise the step of feeding said outputted speed plan to a driver display unit, for at least one of displaying the speed plan for the driver, and informing the driver of suitable speed adaptations based on the speed plan.
Furthermore, according to yet another embodiment of the invention, the method may also comprise the steps of extracting, from a plurality of sensors, sensor information regarding obstacles on or in vicinity of said road section, and generating, based on information from the input connection, the map database, the driver information database, and the sensor information, a speed plan for the current and/or upcoming road section. Thereby, temporary circumstances, or objects not present in the map database, may be taken under consideration when generating the speed plan.
The objects as stated above are also achieved by a system for controlling a vehicle, said vehicle having a cruise control system comprising a position input connection, for receiving vehicle position information from a positioning system, a map database, comprising information regarding at least one of a current and an upcoming road section, based on the vehicle position information, a driver information database, comprising information regarding previous driver behavior for at least one of said current and a similar road section, a speed plan generator, for generating a speed plan for at least one of a current and an upcoming road section, based on information from the input connection, the map database and the driver information database, and an output connection, for outputting the speed plan. By using such a system, it is possible to generate a speed plan, which may be used to adapt the speed of the vehicle for a chosen road section in a desired manner. The speed plan may be used to manually or autonomously control the vehicle. By generating a speed plan for a current and/or upcoming road section, based on map data as well as user preferences as stored in the driver information database, the vehicle may driven in a comfortable and safe way as experienced by the driver.
Furthermore, the system preferably comprising a computing device for generating a driver behavior model, based on information from the input connection, the map database and the driver information database, whereby the speed plan is generated from said driver behavior model. Moreover, said computing device is suitably realized by means of a neural network. This makes it possible to predict speed plans for roads never driven before, by relating it to other road sections having similar road attributes, as stored in the map database.
Finally, the speed plan is outputted to at least one of a throttle control device, a brake system control device and a driver display unit, for enabling autonomous and/or manual control of said vehicle, based on said speed plan.